Re: 2.6.13 new option timer frequency

From: Lee Revell
Date: Mon Aug 29 2005 - 13:14:34 EST


On Mon, 2005-08-29 at 18:57 +0100, Nick Warne wrote:
> Hi all,
>
> I built and installed 2.6.13 today, and oldconfig revealed the new option for
> timer frequency.
>
> I searched the LKML on this, but all I found is the technical stuff - not
> really any layman solutions.
>
> Two n00b questions here:
>
> What does this do/what is it for?
>

Selects the frequency of the timer interrupt. This controls the timing
resolution of system calls. So previously poll/select could be used
with a 1ms timeout. Now with the default settings it can only do 4ms.

> I selected default, 250Hz. If this is now an option, what was it before?

The previous value was 1000HZ. And yes, changing the default from 1000
to 250 breaks the expected "make oldconfig" behavior. Lots of people
are not happy about it, but were overruled by Linus.

Lee

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